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view tests/test-encoding.t @ 38732:be4984261611
merge: mark file gets as not thread safe (issue5933)
In default installs, this has the effect of disabling the thread-based
worker on Windows when manifesting files in the working directory. My
measurements have shown that with revlog-based repositories, Mercurial
spends a lot of CPU time in revlog code resolving file data. This ends
up incurring a lot of context switching across threads and slows down
`hg update` operations when going from an empty working directory to
the tip of the repo.
On mozilla-unified (246,351 files) on an i7-6700K (4+4 CPUs):
before: 487s wall
after: 360s wall (equivalent to worker.enabled=false)
cpus=2: 379s wall
Even with only 2 threads, the thread pool is still slower.
The introduction of the thread-based worker (02b36e860e0b) states that
it resulted in a "~50%" speedup for `hg sparse --enable-profile` and
`hg sparse --disable-profile`. This disagrees with my measurement
above. I theorize a few reasons for this:
1) Removal of files from the working directory is I/O - not CPU - bound
and should benefit from a thread pool (unless I/O is insanely fast
and the GIL release is near instantaneous). So tests like `hg sparse
--enable-profile` may exercise deletion throughput and aren't good
benchmarks for worker tasks that are CPU heavy.
2) The patch was authored by someone at Facebook. The results were
likely measured against a repository using remotefilelog. And I
believe that revision retrieval during working directory updates with
remotefilelog will often use a remote store, thus being I/O and not
CPU bound. This probably resulted in an overstated performance gain.
Since there appears to be a need to enable the thread-based worker with
some stores, I've made the flagging of file gets as thread safe
configurable. I've made it experimental because I don't want to formalize
a boolean flag for this option and because this attribute is best
captured against the store implementation. But we don't have a proper
store API for this yet. I'd rather cross this bridge later.
It is possible there are revlog-based repositories that do benefit from
a thread-based worker. I didn't do very comprehensive testing. If there
are, we may want to devise a more proper algorithm for whether to use
the thread-based worker, including possibly config options to limit the
number of threads to use. But until I see evidence that justifies
complexity, simplicity wins.
Differential Revision: https://phab.mercurial-scm.org/D3963
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Wed, 18 Jul 2018 09:49:34 -0700 |
parents | 035af48b2903 |
children | 89630d0b3e23 |
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Test character encoding $ hg init t $ cd t we need a repo with some legacy latin-1 changesets $ hg unbundle "$TESTDIR/bundles/legacy-encoding.hg" adding changesets adding manifests adding file changes added 2 changesets with 2 changes to 1 files new changesets 1e78a93102a3:0e5b7e3f9c4a (run 'hg update' to get a working copy) $ hg co 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ $PYTHON << EOF > f = open('latin-1', 'wb'); f.write(b"latin-1 e' encoded: \xe9"); f.close() > f = open('utf-8', 'wb'); f.write(b"utf-8 e' encoded: \xc3\xa9"); f.close() > f = open('latin-1-tag', 'wb'); f.write(b"\xe9"); f.close() > EOF should fail with encoding error $ echo "plain old ascii" > a $ hg st M a ? latin-1 ? latin-1-tag ? utf-8 $ HGENCODING=ascii hg ci -l latin-1 transaction abort! rollback completed abort: decoding near ' encoded: \xe9': 'ascii' codec can't decode byte 0xe9 in position 20: ordinal not in range(128)! (esc) [255] these should work $ echo "latin-1" > a $ HGENCODING=latin-1 hg ci -l latin-1 $ echo "utf-8" > a $ HGENCODING=utf-8 hg ci -l utf-8 $ HGENCODING=latin-1 hg tag `cat latin-1-tag` $ HGENCODING=latin-1 hg branch `cat latin-1-tag` marked working directory as branch \xe9 (esc) (branches are permanent and global, did you want a bookmark?) $ HGENCODING=latin-1 hg ci -m 'latin1 branch' $ hg -q rollback $ HGENCODING=latin-1 hg branch \xe9 (esc) $ HGENCODING=latin-1 hg ci -m 'latin1 branch' $ rm .hg/branch hg log (ascii) $ hg --encoding ascii log changeset: 5:a52c0692f24a branch: ? tag: tip user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: latin1 branch changeset: 4:94db611b4196 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: Added tag ? for changeset ca661e7520de changeset: 3:ca661e7520de tag: ? user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: utf-8 e' encoded: ? changeset: 2:650c6f3d55dd user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: latin-1 e' encoded: ? changeset: 1:0e5b7e3f9c4a user: test date: Mon Jan 12 13:46:40 1970 +0000 summary: koi8-r: ????? = u'\u0440\u0442\u0443\u0442\u044c' changeset: 0:1e78a93102a3 user: test date: Mon Jan 12 13:46:40 1970 +0000 summary: latin-1 e': ? = u'\xe9' hg log (latin-1) $ hg --encoding latin-1 log changeset: 5:a52c0692f24a branch: \xe9 (esc) tag: tip user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: latin1 branch changeset: 4:94db611b4196 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: Added tag \xe9 for changeset ca661e7520de (esc) changeset: 3:ca661e7520de tag: \xe9 (esc) user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: utf-8 e' encoded: \xe9 (esc) changeset: 2:650c6f3d55dd user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: latin-1 e' encoded: \xe9 (esc) changeset: 1:0e5b7e3f9c4a user: test date: Mon Jan 12 13:46:40 1970 +0000 summary: koi8-r: \xd2\xd4\xd5\xd4\xd8 = u'\\u0440\\u0442\\u0443\\u0442\\u044c' (esc) changeset: 0:1e78a93102a3 user: test date: Mon Jan 12 13:46:40 1970 +0000 summary: latin-1 e': \xe9 = u'\\xe9' (esc) hg log (utf-8) $ hg --encoding utf-8 log changeset: 5:a52c0692f24a branch: \xc3\xa9 (esc) tag: tip user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: latin1 branch changeset: 4:94db611b4196 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: Added tag \xc3\xa9 for changeset ca661e7520de (esc) changeset: 3:ca661e7520de tag: \xc3\xa9 (esc) user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: utf-8 e' encoded: \xc3\xa9 (esc) changeset: 2:650c6f3d55dd user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: latin-1 e' encoded: \xc3\xa9 (esc) changeset: 1:0e5b7e3f9c4a user: test date: Mon Jan 12 13:46:40 1970 +0000 summary: koi8-r: \xc3\x92\xc3\x94\xc3\x95\xc3\x94\xc3\x98 = u'\\u0440\\u0442\\u0443\\u0442\\u044c' (esc) changeset: 0:1e78a93102a3 user: test date: Mon Jan 12 13:46:40 1970 +0000 summary: latin-1 e': \xc3\xa9 = u'\\xe9' (esc) hg tags (ascii) $ HGENCODING=ascii hg tags tip 5:a52c0692f24a ? 3:ca661e7520de hg tags (latin-1) $ HGENCODING=latin-1 hg tags tip 5:a52c0692f24a \xe9 3:ca661e7520de (esc) hg tags (utf-8) $ HGENCODING=utf-8 hg tags tip 5:a52c0692f24a \xc3\xa9 3:ca661e7520de (esc) hg tags (JSON) $ hg tags -Tjson [ { "node": "a52c0692f24ad921c0a31e1736e7635a8b23b670", "rev": 5, "tag": "tip", "type": "" }, { "node": "ca661e7520dec3f5438a63590c350bebadb04989", "rev": 3, "tag": "\xc3\xa9", (esc) "type": "" } ] hg branches (ascii) $ HGENCODING=ascii hg branches ? 5:a52c0692f24a default 4:94db611b4196 (inactive) hg branches (latin-1) $ HGENCODING=latin-1 hg branches \xe9 5:a52c0692f24a (esc) default 4:94db611b4196 (inactive) hg branches (utf-8) $ HGENCODING=utf-8 hg branches \xc3\xa9 5:a52c0692f24a (esc) default 4:94db611b4196 (inactive) $ echo '[ui]' >> .hg/hgrc $ echo 'fallbackencoding = koi8-r' >> .hg/hgrc hg log (utf-8) $ HGENCODING=utf-8 hg log changeset: 5:a52c0692f24a branch: \xc3\xa9 (esc) tag: tip user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: latin1 branch changeset: 4:94db611b4196 user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: Added tag \xc3\xa9 for changeset ca661e7520de (esc) changeset: 3:ca661e7520de tag: \xc3\xa9 (esc) user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: utf-8 e' encoded: \xc3\xa9 (esc) changeset: 2:650c6f3d55dd user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: latin-1 e' encoded: \xc3\xa9 (esc) changeset: 1:0e5b7e3f9c4a user: test date: Mon Jan 12 13:46:40 1970 +0000 summary: koi8-r: \xd1\x80\xd1\x82\xd1\x83\xd1\x82\xd1\x8c = u'\\u0440\\u0442\\u0443\\u0442\\u044c' (esc) changeset: 0:1e78a93102a3 user: test date: Mon Jan 12 13:46:40 1970 +0000 summary: latin-1 e': \xd0\x98 = u'\\xe9' (esc) hg log (dolphin) $ HGENCODING=dolphin hg log abort: unknown encoding: dolphin (please check your locale settings) [255] $ HGENCODING=ascii hg branch `cat latin-1-tag` abort: decoding near '\xe9': 'ascii' codec can't decode byte 0xe9 in position 0: ordinal not in range(128)! (esc) [255] $ cp latin-1-tag .hg/branch $ HGENCODING=latin-1 hg ci -m 'auto-promote legacy name' Test roundtrip encoding of lookup tables when not using UTF-8 (issue2763) $ HGENCODING=latin-1 hg up `cat latin-1-tag` 0 files updated, 0 files merged, 1 files removed, 0 files unresolved $ cd .. Test roundtrip encoding/decoding of utf8b for generated data #if hypothesis >>> from hypothesishelpers import * >>> from mercurial import encoding >>> roundtrips(st.binary(), encoding.fromutf8b, encoding.toutf8b) Round trip OK #endif